3GPP2 standards are being developed to support femtocells, which employ small base stations with a small coverage area. Femtocells might be sold by licensed operators and might operate in licensed bands. A femtocell might connect to the operator's network through an untrusted broadband connection subscribed by the user. A typical use case would be for a user to install a femtocell in his home. The femtocell would serve the user's mobile devices while at home, but would typically not serve visiting mobile devices. Visiting mobile devices are typically not authorized to use the femtocell, so it would be best to avoid having these mobile devices attempting to use the femtocell at all.
An existing approach is for the network infrastructure to manage a blacklist for a mobile device indicating femtocells that the mobile device is not to use. The mobile device downloads the blacklist to make it aware of femtocells that it is not to use. This existing approach is undesirable because it is complex for the network infrastructure to manage blacklists and provide the same to mobile devices. Also, downloading the blacklist occupies network interface capacity, especially if downloading updates to the blacklist on an ongoing basis.
There is another approach in which a static blacklist is provisioned into the mobile devices during manufacturing. The network operators plan their macro network accordingly such that subscribers that are not subscribing to femtocells will use the static blacklist and avoid selecting femtocells. The disadvantage of this approach is its inflexibility. Also, this approach involves a lot of advanced network planning. In addition, if femtocells become very popular, there is no way for a carrier to increase the number of femtocells available to its subscribers.